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The Javanese calendar (Javanese: ꦥꦤꦁꦒꦭ꧀ꦭꦤ꧀ꦗꦮ, romanized: Pananggalan Jawa) is the calendar of the Javanese people. It is used concurrently with two other calendars, the Gregorian calendar and the Islamic calendar. The Gregorian calendar is the official calendar of the Republic of Indonesia and civil society, while the Islamic calendar is used by Muslims and the Indonesian government for religious worship and deciding relevant Islamic holidays.
The Javanese calendar is used by the main ethnicities of Java island—that is, the Javanese, Madurese, and Sundanese people—primarily as a cultural icon and identifier, and as a maintained tradition of antiquity. The Javanese calendar is used for cultural and spiritual purposes.
The current system of the Javanese calendar was inaugurated by Sultan Agung of Mataram in the Gregorian year 1633 CE. Prior to this, the Javanese had used the Śaka calendar, which has its epoch in 78 CE and uses the lunisolar cycle for calculating time. Sultan Agung's calendar retained the Saka calendar year system of counting, but differs by using the same lunar year measurement system as the Islamic calendar, rather than the solar year. Occasionally, the Javanese calendar is referred to by its Latin name Anno Javanico or AJ (Javanese Year).